Contrast-enhanced ultrasonography in the diagnosis of solid renal tumors.

OBJECTIVE: The purpose of this study was to evaluate the usefulness of contrast-enhanced ultrasonography (CEUS) in the diagnosis of solid renal tumors. METHODS: Twenty-nine patients with solid tumors detected on gray scale ultrasonography underwent resection for suspected renal malignancy. Findings of arterial phase contrast computed tomography (CT) and CEUS were compared for each diagnosis. RESULTS: Histopathologic examination of resected lesions showed malignancy in 26 patients (clear cell carcinoma, n = 18; papillary renal cell carcinoma, n = 6; collecting duct carcinoma, n = 1; and infiltrative urothelial carcinoma, n = 1) and benign tumors in 3 patients (oncocytoma, n = 2; and angiomyolipoma, n = 1). Contrast CT failed to show tumor blood flow in 5 of 29 patients, whereas CEUS showed this in all patients. Positive predictive values of CEUS and contrast CT in the diagnosis of renal malignancy were 100% and 82.8%, respectively. Among clear cell carcinomas, hypervascularity was observed on contrast CT in 16 of 18 patients and on CEUS in 17 of 18 patients. On the basis of hypervascularity, diagnostic sensitivity values for clear cell carcinoma were 94.4% for CEUS and 88.9% for contrast CT, whereas specificity values were 45.5% for CEUS and 72.7% for contrast CT. Among papillary cell carcinomas, contrast CT showed avascular lesions in 4 of 6 patients. However, CEUS showed blood flow in these lesions, leading to diagnosis of hypovascular renal tumors. CONCLUSIONS: Contrast-enhanced ultrasonography was more sensitive for detecting slight tumor blood flow than contrast CT and was useful in preoperatively diagnosing malignant hypovascular renal tumors but was less so for hypervascular renal tumors.     

Risk factors for surgical site infection after stoma closure comparison between pursestring wound closure and conventional linear wound closure: Propensity score matching analysis

Purpose

Stoma closure has been associated with a high rate of surgical site infection (SSI) and the optimal skin closure method is still controversial. The aim of this study was to compare the short-term and long-term outcomes between the conventional linear closure (CC) and the persestring closure (PC) using propensity score matching analysis.

Effect of obesity on outcomes in patients undergoing implantation of continuous-flow left ventricular assist devices

The purpose of this study was to analyze the effect of obesity on outcomes after continuous-flow left ventricular assist device (CF-LVAD) implantation. A single-center retrospective analysis was performed on 526 chronic heart failure patients who were implanted with the HeartMate II CF-LVAD (n?=?403) or HeartWare HVAD (n?=?123) between November 2003 and March 2016. Patients were stratified into 4 groups based on BMI: underweight (<?18.5 kg/m², n?=?18, 3.4%), normal-weight (18.5–25 kg/m², n?=?173, 32.9%), overweight (25–30 kg/m², n?=?182, 30.2%), and obese (>?30 kg/m², n?=?153, 33.5%). The underweight group was excluded because of its small sample size. Records were reviewed to determine the incidence of postoperative complications and survival. Survival at 1, 6, 12, and 24 months were similar among normal-weight (91.3, 84.4, 76.3, and 67.6%), overweight (90.4, 80.8, 76.5, and 69.6%), and obese patients (90.7, 74.7, 65.3, and 61.3%, p?=?0.24). Additionally, obesity was not a significant predictor of mortality in Cox proportional hazard models (hazard ratio 0.98, 95% confidence interval 0.766–1.277, p?=?0.13). These findings suggest that appropriately selected obese patients receive similar survival benefit from CF-LVADs compared to non-obese patients, and obesity should not serve as a contraindication to CF-LVAD implantation.     

HeartMate II implantation technique that spares the sternum and ascending aorta

Left ventricular assist devices (LVADs) have become the standard therapy for patients with end-stage heart failure, and the use of LVADs for long-term support has grown exponentially over the past decade. As the number of LVAD implantations has increased, surgeons have faced more challenging cases, such as those in which the patient has previously undergone a sternotomy. The HeartMate II is one of the most widely implanted LVADs. The standard procedure for HeartMate II implantation is median sternotomy and sewing the outflow graft to the ascending aorta. However, in patients with sternal comorbidities, it can be advantageous to use a less invasive approach that avoids this procedure. We describe the case of a 64-year-old man with a history of end-stage ischemic cardiomyopathy who had previously undergone a median sternotomy and a coronary artery bypass grafting operation and had patent grafts. He required a HeartMate II LVAD (destination therapy), which was implanted via a left subcostal incision; the pump was placed subdiaphragmatically, and the outflow graft was sewed to the descending aorta to avoid a complicated redo cardiac operation via median sternotomy and to minimize the risk of injuring the patent bypass grafts. The patient survived for more than 500 days postoperatively. This approach is feasible and could be a safer method for implanting a HeartMate II device in patients with serious comorbidities that preclude the use of the traditional implantation techniques.     

Three‐dimensional structures of bacteriophage neck subunits are shared in Podoviridae,Siphoviridae and Myoviridae

Tailed bacteriophages (Caudovirales) are divided into three families: Myoviridae with long contractile tails, Siphoviridae with long noncontractile tails and Podoviridae with short noncontractile tails. All have an icosahedral head with a portal vertex connected to a neck structure followed by a tail. Bacteriophage Mu belongs to the Myoviridae family. Herein, the gp29 portal subunit and neck subunits gp35, gp36 and gp37 of the Mu phage were purified to elucidate their arrangement in the neck. Both gp29 and gp36 were monomeric in solution, like the corresponding subunits of Podoviridae P22 and Siphoviridae SPP1. X‐ray crystal structure of gp36 showed structural similarity to neck subunits of Siphoviridae and Podoviridae. The gp36 structure has a characteristic aromatic hydrophobic core, and the structure of the ring form of the Mu phage connector deduced from the Siphoviridae and Podoviridae connector showed that this feature builds the contact surface between gp36 subunits. Structural comparison with the neck of Siphoviridae and Podoviridae also implies direct interaction between gp36 and gp29. Because gp35 and gp36 form a stable complex, we predict that the head‐portal ring (gp29), the connector complex (gp36 and gp35), the tail terminator (gp37) and the tube (gp40) are arranged in the Mu phage neck in this order.     

Clinical significance of measurement of plasma annexin V concentration of patients in the emergency room

Annexin V, a calcium-binding protein, is widely present in various organs and tissues. In the present study, plasma annexin V concentration was measured in 158 patients who were brought to the emergency room, including 25 patients suffering from acute myocardial infarction (AMI), 14 with cerebrovascular disease, 11 with trauma of the extremities, 11 with severe trauma associated with visceral damage, and 35 with witnessed cardiac arrest. Annexin V concentration in normal healthy individuals (n=110) was 1.9+/-0.7 ng/ml. Annexin V concentration in AMI and cardiac arrest patients was 11.0+/-4.9 and 15.3+/-7.9 ng/ml, respectively, being significantly higher than that in patients with cerebrovascular disease (5.4+/-2.7 ng/ml). The value in severe trauma patients was 15.9+/-9.4 ng/ml, being significantly higher than that in patients with trauma of the extremities (5.6+/-1.2 ng/ml). Annexin V concentrations in the cardiac arrest and AMI patients who survived more than 24 h after admission were lower than those in patients who died within 24 h after the onset of symptoms. Annexin V content in the lungs and myocardium in normal rats was extremely high in comparison to that in brain and skeletal muscle. These results suggest that the high levels of plasma annexin V in patients with AMI, cardiac arrest and severe trauma reflect the severity of damage of the myocardium and/or other visceral organs, and measurement of plasma annexin V concentration may help to assess the prognosis of patients brought to the emergency room.     

Enhanced tumor cell selectivity of adriamycin-monoclonal antibody conjugate via a poly(ethylene glycol)-based cleavable linker.

A novel linker consisting of poly(ethylene glycol) (PEG) and dipeptide was used for conjugation of adriamycin with tumor-specific monoclonal antibody, NL-1, to confirm that the linker can be cleaved selectively with the tumor specific enzyme to express cytotoxicity of the anti-tumor agent. Initially, adriamycin-conjugated PEG linkers through different amino acid compositions, alanyl-valine (Ala-Val), alanyl-proline (Ala-Pro), and glycyl-proline (Gly-Pro) sequences, were prepared to confirm selective digestion with model enzymes. Adriamycin was released by particular model endoproteases, thermolysin and proline endopeptidase, from the linkers with different efficiency. When conjugates were prepared using these adriamycin-bound linkers, conjugates had no loss of binding affinity and specificity for common acute lymphoblastic leukemia antigen (CALLA) expressed on the Daudi cell surfaces as the target of NL-1 antibody. In addition, adriamycin release from the conjugates was also confirmed by incubating them with specific proteases. Tumor cell growth was inhibited dose-dependently for the conjugates carrying Ala-Val and Gly-Pro linkers, whereas significant inhibitory effect was abolished for the conjugate carrying Ala-Pro linker, indicating that cytotoxic effect can be controlled by specificity of antibody and composition of linker peptide. IC(50) for Ala-Val linked conjugate was approximately 3.5 microg/ml and that for Gly-Pro linked conjugate was 5.2 microg/ml. PEG-dipeptidyl linker demonstrated here will be an effective tool for the preparation of immunoconjugate, especially specific activation of anti-tumor agents at desired tumor tissues.